Yes, changing the airflow through your engine in any way may sometimes force you to do a remap , as some cars may give out fault codes due to the increase in air flow, a remap will tell the ECU better what to do with all the extra air flow, some ECU's are better than others coping with changes in the air flow but ultimately a remap is best for power gains. So the ultimate thing to do would be a cold air intake system coupled with a performance filter followed by freeing up air on the outlet by performance outlet manifold, freeflow exhaust and a decat pipe or sports cat.